Hello !

I have a simple question : what can I do if a new operator or make_unique fail to allocate and crash ?

How can I avoid a crash and allocate without any problem ?

theScore said:
I have a simple question : what can I do if a new operator or make_unique fail to allocate and crash ?

ask the government to help -lol-

anyway; try this:

std::unique_ptr<MyCameraClass> c;
c = std::make_unique<MyCameraclass>(arg1, arg2); // it will use new internally

hope this helps ?

It is ever the code I am using, it crashes on the line of the make_unique instruction.

Do you think it could be a problem of memory fragmentation ? I am doing a lot of allocation/deallocation with this pointer.

theScore said:
Do you think it could be a problem of memory fragmentation ?

it sounds like you have overloaded the new operator to use a custom memory pool allocator, if this is the case then yes you need to check how you're allocation/deallocating your pool chunks in your pool allocator (pointer violation or what not…);

if you're not using a custom allocator then check the constructors of the class you are trying to instantiate;

you can also try this (make sure you have exceptions throwing enabled for this to work):

// pseudo
try
{
 ... code i gave u OR your code ...
}
catch(std::exception* e) // OR catch(std::exception& e) whichever works for u
{
  ... log problem here
}

u may have to do the same thing in your pool allocator, if it has exception-throwing ability;

in all cases the code i gave u will never crash on its own merit, it is standard code ?

That's it … all the best ?

Thanks, but I have a question : how to do for implement a pool allocator ? Do you know a good website which explain this ?

theScore said:
how to do for implement a pool allocator ? Do you know a good website which explain this ?

the explanation would be too long for this post, so take a look here:

• here:
• https://www.modernescpp.com/index.php/memory-pool-allocators-with-jonathan-mueller​
• https://github.com/foonathan/memory​
• here:
• http://dmitrysoshnikov.com/compilers/writing-a-pool-allocator/​
• and a good theory here:
• https://www.codeproject.com/Articles/15527/C-Memory-Pool

if the links don't work, just copy-paste them into your browser;

u now have enough to get u going;

Have fun ?

Thank you !

Generally, when -new- operator fails, it's because a memory was bad desallocated before.

For example, “delete [] data” when data is not an array. etc.

Thanks for the answer, I will check my code.